The cost of an adult ticket is x = 9.50
The cost of a child ticket is y = 6.25
Let's find the costs.
We need to solve the system of equations:
2x+5y=50.25
3x+4y=53.50
We want to use the elimination method, so let's take the difference between 3 times the first equation and 2 times the second (so we remove x)
3*(2x + 5y) - 2*(3x + 4y) = 3*50.25 - 2*53.50
15y - 8y = 43.75
7y = 43.75
y = 43.75/7 = 6.25
Then the value of x is:
2x+5y=50.25
2x = 50.25 - 5y
x = (50.25 - 5y)/2
x = (50.25 - 5*6.25)/2
x = 9.5